Ranking member Devin Nunes (R-Calif.) kicked things off by ignoring Alexander Vindman's rank of lieutenant colonel, and other Republicans piled on.
Lt. Col Alexander Vindman and State Department official Jennifer Williams testified about their concerns with President Trump's call with Ukrainian President Zelensky.
The Senate majority leader is likely to abandon the president if it appears that keeping his role is more assured if Trump is gone.
Former national security adviser Susan Rice called the claims of White House press secretary Stephanie Grisham "a bald-faced lie."
Critics pointed out that Lt. Col. Alexander Vindman is a decorated combat veteran, while Trump recently fled a book signing "because people were being mean."
Several top officials with potentially valuable knowledge have refused to come to Capitol Hill.
Kurt Volker said he has known former Vice President Joe Biden as an honorable man for decades while rebuffing debunked corruption allegations.
Lt. Col. Alexander Vindman's counsel was forced to step in during the awkward moment.
The former National Security Council expert on Russia testifies that he "didn’t necessarily always act" on EU ambassador Gordon Sondland's ideas.
The former special envoy to Ukraine is one of many establishment Republicans who tried in vain to change the Trump administration from within.
“Who are we as a nation if we respond to threats of political retribution with retribution?” the congresswoman wrote in a letter.
"The president gets to choose who’s around him, but I don’t think that reflects as well as it might,” the senator said of Miller's apparent ties to white nationalism.
Trump's lawyers are expected to keep fighting the lawsuit.
Lt. Col. Alexander Vindman said he believes Trump offered Ukraine little choice if it wanted to receive U.S. military aid.
“I’m an American,” the Army lieutenant colonel said in impeachment proceedings. “I came here when I was a toddler. I immediately dismissed these offers.”
Media outlets mention that Pete Buttigieg was a Rhodes scholar far more often than they mention that Cory Booker was one too.
The White House adviser and white nationalist worked with the far-right publication to smear the Florida senator ahead of the 2016 election.
Read live updates as the top Ukraine expert for the National Security Council and an aide to Mike Pence are questioned by the House Intelligence Committee.